Acid-proof cementing compositions



we. UUMIUSIHONS,

COATING R PLASTIC.

Patented July 12, 1932 KARL DIETZ Alll'lD KARL FRANK, OF FRANKFORT-ON-THE-MAIN-HOCHST, GERMANY, AS- SIGNORS TO I. G. FARBENINDUSTRIE AKTIENGESELLSCHAFT, 0F FRANKFURT-ON- THE-MAIN, GERMANY ACID-PROOF CEMENTING COMPOSITIONS No Drawing. Application filed January 23, 1931, Serial No. 510,841, and in Germany July 30, 1925.

The present invention relates to acid-proof pends u on the a I cementing compositions. is in en ed. arger quantities of the te- The water-glass cements heretofore known rial are required, use is made of 0: set only gradually when exposed to the acgrained mixtures of sand and chips, where- 5 tion of air. The setting could be promoted by aQ WLLQm-Ete mixtures are obtaine 55 by acidifying, i. e. by coating the cementing compositions with an acid of any kind, or by our invention, but they are not intended to artificially drying them. limit it thereto; we use, for instance, the fol- We have now found that water-glass celowing mixtures:

ments can be prepared which independent @40 grams of Na SiF 940 grams of from the access of air only set by an interquartz, grams of clay and 300 grams of nal chemical reaction if to the water-"lass w er-glass of 38 B. such solid substances are added as 50 grams of K siF 920 grams of pable of reacting with the caustic soda soluquartz, grams of clay and 300 grams of wa- 15 tion of the Water-glass. All these substances ter-glass of 38 B.

must have the same property of reacting This application contains subject matter with the caustic soda solution of the waterin common with our applications Serial Nos. glass, thus forming or separating more or 125.325 and 245.036 filed on July 27, 1926 and less acid-in-soluble solid substances. During January 6, 1928.

20 this operation the silicic acid contained in \Ve claim:

the waterlass is converted into the solid 1. Acid-proof cementing compositions form by tfie elimination of the alkali which consisting of a mixture of water-glass, an

is necessary for keeping the water-glass in a, acid-proof filling agent and a small quantity liquid condition. of an alkali silicon-fluoride.

As such substances there may be used 2. Acid-proof cementing compositions alkali silicon-fluorides, for instance sodium onsisting of a mixture of water-glass, an silicon-fluoride and potassium silicon-lluora id-proof filli ag nt and a mall quantity me. of sodium silicon-fluoride.

F or the preparation of cementing composi- 3. Acid-proof cementing compositions tions these substances are. finely pulverized consisting of a mixture of water-glass, quartz,

and mixed while stirring with the water-glass clay and a small quantity of an alkali siliconsolutions prepared according to known procfluorid esses. Small additions gi-HJflL-cent of 4. Acid-proof cementing compositions these substances are generally sufficient for consisting of a mixture of 300 parts of waterobtaining a self-hardening water-glass ceglass of 38 B., 940 parts of quartz, 20 parts ment. To the cementing compositions there f lay and parts of sodium siliconmay likewise be added such substances as infl id (Na SiF crease the lasticity of the masses. The In t ti ony whereof, w afiix our gigcates 0t alumn'i'a, for instance ulverized t 40 cfia'motte and the like and the sultates 0t KARL DIETZ.

the alkaL I 1e earth metals possess these prop- KARL FRANK. erties. The sillc'o fiuo'i ides are more eflicacious in their reaction than the mineral substances so that they need-enlyiofibmllsed insmall quantities; the cementing compositions may be filled up with indifierent filling agents, such as for instance uartz s. nd J ulverized bi cuit ulverized c amo te an the l ke.

The size of grain of the filling agents do- The 0 owing examples serve to illustrate 

